Hithertobefore, principally, gluten has been produced according to the Martin process or dough-ball process wherein wheat flour is mixed with a volume of water. The resulting mixture is then kneaded into a dough and the dough is allowed to stand for a while until the gluten product and also the starch substance have well been hydrated to form a hydrated flour mass. The hydrated mass is then repeatedly washed with volumes of water further added to separate the vital gluten and the milky starch substance from the dough-like, hydrated flour mass. Alternatively, gluten has been produced according to the Batter process wherein wheat flour is mixed with a larger volume of water and the resulting mixture is then kneaded to form a smooth and elastic batter. This batter is then allowed to stand for a while and subsequently washed with a 2-fold to 5-fold volume of water to give the gluten the form of small curd-like aggregates and the milky starch substance. Next the gluten aggregates and the milky starch substance are separated from each other by passing through a vibrating screen of 60-150 mesh so that the curd-like, vital gluten is recovered.
The conventional vital gluten as produced by the above-mentioned prior art methods generally finds many and different applications, for instance for: the preparation of baked solid wheat gluten based-bread (called "Fu" in Japanese), the production of sodium glutamate as a seasoning agent, the preparation of a gluten hydrolysate containing amino acids for use as an extender for Japanese soy sauce (called "Sho-yu" in Japanese), and the production of new proteinous food products and the like. As one of the many applications of the vital gluten, the addition of the vital gluten to farinaceous bread flour to improve its bread-making properties is also known. However, the effects of the conventional vital gluten for the improvement of the bread-making properties of the farinaceous bread flour are still not satisfactory.
Further, it is also known that some proteinaceous materials are added to the farinaceous bread flour to provide a high protein bread (U.K. Patent Nos. 1,074,087 and 1,472,738, for example) and that one of the modified gluten products comprising the reaction product of vital gluten and xanthan gum or a hydrophobic liquid is added to the farinaceous bread flour in order to improve the properties of the bread product (U.S. Patent Nos. 4,198,438 and 4,396,637).
Furthermore, it is known that an oxidizing agent such as L-ascorbic acid, potassium bromate and others; a reducing agent such as glutathione, cystein and the like; enzymes such as amylase, protease and the like; and an emulsifier such as aliphatic acid esters of glycerine, aliphatic acid esters of saccharide and the like, as well as wheat flour protein such as certain activated gluten are used as the bread improver or bread-improving additive for improving the bread-making properties of the farinaceous bread flour (see, for example, Japanese patent publication No. 29685/86; U.K. Patent No. GB 2126867B; and "Cereal Chemistry" Vol. 57, No. 3, pp. 169-174 (1980); Vol. 58, No. 5, pp. 384-391 (1981), published from The American Association of Cereal Chemists).
These known bread improvers are yet not satisfactory as their effects of improving the properties of bread are not sufficient and as some of the known bread improvers can occasionally give rise to unfavorable flavor and taste of the bread products.
In these circumstances, the demand still exists for new bread improvers which can satisfactorily improve the properties of bread products and other bakery products.
We, the present inventors, have done research in an attempt to provide new bread improvers which can exert satisfactorily the better effects for improving the properties of bread. As a result, we have now found that when the known process of preparing gluten from wheat flour is carried out in such a modified manner that one or more oxidizing agents are added to the raw wheat flour and the resulting mixture is then kneaded with addition of water to form a dough-like or batter-like kneaded mixture of hydrated wheat flour, the oxidizing agent and water, it is possible to recover or separate a new, modified gluten product from said dough-like or batter-like knead mixture. This is done by washing this kneaded mixture repeatedly with water and isolating the water-insoluble gluten fraction from the water-insoluble starch fraction or starchy material and also from the water-soluble fraction existing in said kneaded mixture of the hydrated wheat flour, the oxidizing agent and water. The modified gluten product so recovered or separated is useful as a bread-improver, namely the additive for improving both the bread-making properties of the flour and the properties of bread or other bakery products, such as the volume, the crumb structure or texture, the crumb smoothness or chewing mouth feel and the external appearance of bread.
Further, we have now found that when the above-mentioned new modified gluten product is recovered or separated from the dough-like or batter-like kneaded mixture of the hydrated flour, the oxidizing agent and water, it is also possible to recover separately a water-soluble proteinaceous fraction or substance from the water-insoluble starch fraction or substance existing in said dough-like or batter-like kneaded mixture. This water-soluble proteinaceous fraction or substance so recovered is also useful as an additive for improving the properties of the wheat flours and the bread products or other bakery products as prepared from the flours. It also has been found that this water-soluble proteinaceous substance so recovered can exert their effects of improving the properties of wheat flours and bread to a satisfactory extent especially when this substance is incorporated to the farinaceous bread flour at a smaller proportion than said new water-insoluble, modified gluten product now prepared by the present inventors.
On the other hand, in recent years, various machines such as the dough divider, rounder, molding machine and so on have been employed in the process of making bread in large scale. Particularly, the dividing and scaling of the dough into small balls or masses and the making-up of these small masses of the dough are conducted by machines rather than by hands of men. However, when the dough masses have been divided, scaled and made-up by the mechanical working of the machines, it is likely that the bread products as prepared by baking such mechanically worked dough show a reduced volume and a reduced crumb texture, as compared to the bread products which are prepared from the hands-worked dough. Accordingly, it is desirable that the dough for making the bread is tolerant to the mechanical workings in the sense that the bread as prepared even by baking the mechanically worked dough can still give a satisfactorily large volume and good crumb structure or texture as much as the bread as prepared from the hand-worked dough. Therefore, there exists a great demand for a new bread improver which can provide a bread-making dough tolerant to the mechanical workings in the above sense.
As one result of our research, we have now found that a proteinaceous composition comprising a mixture of the above-mentioned new modified gluten product and the above-mentioned water-soluble proteinaceous fraction or substance which both have been separated from the aforesaid kneaded mixture of the hydrated wheat flour, the oxidizing agent and water is again useful as a new bread improver which can provide the bread-making dough tolerant to the mechanical workings in the sense described above.
This invention has been accomplished on the basis of the above findings of the present inventors.